Born in Sliven, Vandev started to play football at local club Sliven 2000. He made his debut for the first team in 2001, in the Bulgarian amateur division. After a series of good displays, Vandev caught the eye of Lokomotiv Plovdiv scouts and he signed for "Loko" in the early 2003. The forward made his official debut in the Bulgarian first division on 13 March 2004 in a match against Chernomorets Burgas as a 62nd-minute substitute. In the same year Vandev won the Bulgarian Championship title with Lokomotiv. He played for the team from Plovdiv for five seasons.